GUADALAJARA, Mexico – SpaceX CEO Elon Musk has made some ambitious sales pitches in his career, but today’s big reveal about his plan to transport a million settlers to Mars over the next few decades has to be the topper.

The billionaire began his 95-minute talk with the existential concern over Earth’s long-term future, and the need to set up a civilization beyond Earth to safeguard the species.

“I hope you’d agree this is the right way to go. Yes? … That’s what we want,” he told a crowd of 3,000 attendees at the International Astronautical Congress in Guadalajara.

From there on, Musk laid out a step-by-step blueprint that culminated in a vision of a totally reusable super-spaceship that could transport 100 to 200 passengers and their luggage to the Red Planet.

The Interplanetary Transport System that Musk proposes is even bigger than the pre-reveal rumors suggested. It would stand 400 feet tall, with a massive, 55-foot-wide spaceship at the top.

The ITS rocket would be taller and wider than the Saturn V rocket that sent astronauts to the moon, and more than three times as powerful. Each booster rocket would use 42 of SpaceX’s Raptor rocket engines, and there’d be nine more Raptors on the passenger spaceship.

Depending on the options for in-flight refueling, Musk figures the fully reusable launch system could send 450 tons of payload to Mars at a cost of $140,000 per ton.

“It’s quite big. … I think in the long term, the ships will be even bigger than this,” he said.

And we’re not talking about just one of these monsters: Musk’s math calls for building 1,000 passenger spaceships that would go on a total of 10,000 trips over the course of 40 to 100 years. That’s what it would take to get a million settlers to Mars, which Musk figures would be the requirement for creating a permanent human presence on Mars.

This graphic shows the architecture for Elon Musk’s interplanetary transport system. Click on the image for a bigger version. (Credit: SpaceX)

Because of orbital mechanics, the best time to travel from Earth to Mars comes every 26 months – and that’s the main reason why the schedule has to be so spread out. After reaching orbit, the spaceships would be refueled by tankers for the trip to Mars, and methane would be manufactured on Mars for the return flight.

The journey would take 80 to 150 days, depending on orbital mechanics. He said the passenger compartment should have zero-G game facilities, restaurants and other amenities that would make it “really fun to go.”

In order to make the trip affordable, Musk said the cost of a trip to Mars should be in the realm of the price tag for the average U.S. home, which he pegged at $200,000. The ticket price could come down to “maybe as little as $100,000 over time, depending upon how much mass a person takes.”

The cost could include the promise of a free return trip to Earth if settlers so chose. “I think it’s pretty important to give people the option of returning … even if they never actually return,” Musk told the crowd.

But would-be settlers will still have to take their chances. Musk acknowledged that “the risk of fatality would be high,” particularly in the early stages of migration.

Musk pointed out that the Interplanetary Transport System could be used for other deep-space destinations all the way out to the comet-laden Oort Cloud, as long as there were filling stations along the way. “You can make flights from Mars to Jupiter, no problem. … It’d be really great to do missions to Europa,” he said.

An artist’s conception shows the Interplanetary Transport System on Europa, one of Jupiter’s moons. (Credit: SpaceX)

Right now, SpaceX is spending a “few tens of millions of dollars” annually on development of the Mars transport concept, which amounts to well under 5 percent of the company’s total expenses, Musk said.

A lot of that money is going toward the development of the technologies that will be required, such as SpaceX’s methane-fueled Raptor rocket engine and the carbon-fiber tanks for the rocket’s propellants. Musk said that SpaceX engineers had been working seven days a week to demonstrate those technologies in time for his Guadalajara presentation.

As time goes on, Musk expects to spend more and more on the Mars effort – perhaps as much as $300 million a year by 2018 or so. The costs of preparing for the first launch to Mars would “probably be on the order of $10 billion,” he said.

That first launch could take place in about 10 years “if things go super-well,” Musk said.

Musk had no problem making the sale in the lecture hall at the Guadalajara Expo complex. The applause was long and warm when Musk said “life needs to be more than just solving problems today.” But the road to Mars isn’t likely to be as smooth as the CGI graphics make it seem.

Musk provided little detail on how astronaut selection and training would be handled. In response to one question, he conjectured that “maybe a few days of training would be required.” And he didn’t address what settlers would do once they got to Mars.

Then there’s the funding question: During his presentation, Musk joked that his strategy for raising money might be to “steal underpants,” do a Kickstarter campaign … and profit. Others options include relying on the revenue from SpaceX’s other operations, ranging from resupplying the International Space Station to putting satellite constellations into orbit.

Musk acknowledged that the push for Mars would ultimately have to rely on public-private partnerships. “That’s how the United States was established, and many other countries around the world,” he said.

NASA is already cooperating with SpaceX on a range of space endeavors, including a robotic “Red Dragon” mission to Mars that could take off as early as 2018. But NASA has its own blueprints for Mars missions, which depend on a heavy-lift rocket as the Space Launch System. The SLS rocket is due to have its first test flight in 2018, and NASA plans to send astronauts to Mars and its moons in the 2030s.

It’s not clear how Musk’s plans for the ITS will mesh with NASA’s plans. SpaceX’s most ardent fans might wish that NASA would drop their heavy-lift launch program and leave the driving to Musk. But today, Musk called himself “NASA’s biggest fan,” and representatives of the space agency returrned the compliment in a smattering of tweets:

Mars Society President Robert Zubrin, who has been advocating human missions to Mars for decades, said in a Facebook posting that Musk presented “a number of interesting and very useful ideas.”

“I don’t think they are practical in the form he presented them. But with a little modification, they could be made practical and very powerful,” Zubrin said. He added that there might even be a way to do the job with SpaceX’s Falcon Heavy rocket, which is expected to make its debut next year.

In an interview with GeekWire, Zubrin said Musk’s blueprint should serve as a “spur to action” for NASA officials. “They are being ‘Sputniked,’ and they need to rise to the challenge,” he said.

In his talk, Musk made clear that sending settlers to Mars, and turning humanity into a multiplanetary species, was his life’s work. Even his role as the CEO of Tesla Motors, which makes electric cars and batteries, apparently takes a back seat to Mars.

“As we show that this is possible … not just a dream, it’s something that can be made real, I think the support will snowball over time,” said Musk, whose net worth is currently estimated at $11.7 billion. “And I should say also, the main reason I’m personally accumulating assets is in order to fund this.”

Tip o’ the Hat to John Gardi for helping me iron out the details of Musk’s plan.

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